Grapeview Point Boat Works

81 E Grapeview Point Rd + Allyn, WA 98524 + 360-277-9015 + boat_works@yahoo.com

Building a Glued Lapstrake Rangeley Lake Boat

Page 3: Building the Ladder Frame and Molds

The new ladder frame
The new ladder frame

We built a new ladder frame for this boat. The ladder frame will support the stations molds that determine the hull's shape.

The station molds are made of pine since it is cheap and easy to work. The shape of each part is picked up from the lofted body plan by placing 3d nails along the outline, and then pressing the pine onto the nail heads. This leaves indentations in the wood, which are connected using a pencil and batten so that the part can be cut to shape on the band saw.

Transferring the mold shape to the pine mold
Transferring the mold shape to the pine mold

On large boats, the body plan is lofted on the floor, and the parts are walked on to press the nails into the wood. It's nice to think that in the age of laser guided tools and digital readouts that the nail is still the preferred method. Score one point for the Luddites.

Duplicating mold parts so that port and starboard are symmetrical
Duplicating mold parts so that port and starboard are symmetrical

There is a duplicate required for each part of a mold (one port, one starboard), so the final shaping of each pair is done with a block plane and spokeshave while they are held in a vise.

The mold for station four
The mold for station four

The mold parts are glued and nailed together while arranged on the body plan. This ensures that the molds accurately reflect the lofting, and that both sides of each mold are identical. There is no point being careful with the lofting, only to get sloppy with the mold construction...

The notch at the center of the mold will locate the keelson.

The completed molds
The completed molds before being installed on the ladder frame

These are all the molds needed to build this boat. Now the shape of the hull starts to become apparent. Note how flat the bottom is at the mid-section!

Sometimes molds are made out of plywood to save a little time, especially if only one hull will be built using them. Pine molds will hold up better for future hulls. It's easier to reach inside the boat with the built-up molds, also.




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